August 3rd, 2012
12:31 PM ET

Mars landing will be ‘seven minutes of terror’

Program note: Tune in to and CNN Mobile for live coverage of the Curiosity's landing on Mars, starting at 11:30 p.m. ET Sunday.

The future of Mars exploration is, at least in the short term, riding, pardon the pun, quite literally on a two thousand pound car sized rover called Curiosity.

The weight of the two and a half billion dollar mission, called the Mars Science Lab, is not lost on the scientists and engineers at NASA’s Jet Propulsion Laboratory in California who built Curiosity. Mission Chief Engineer Rob Manning doesn’t sugar coat it. “If it does fail is that the end of exploration? Well, it may be the end for awhile. It may require a stop and regroup. Certainly it will.”

Engineer Adam Steltzner is in charge of EDL, that’s the Entry, Descent and Landing phase of the mission. “Full nights of sleep have eluded me for a couple of years now,” says Steltzner.

Why the anxiety? NASA has a good track record landing vehicles on Mars. What is so different this time around? Well, other than the planet, just about everything is different. In fact, the landing method has never been tried before. It is so unique and complicated the Space Agency has dubbed it, “Seven minutes of terror.” From the time Curiosity touches the top of the Martian atmosphere to the time it lands is seven minutes.

In the past, NASA has used either legged landers or has tucked its rovers inside giant airbags that would bounce along the Martian surface. But Curiosity is too big to be stuffed inside an airbag cocoon. And, where it is going requires a far more precision landing than every attempted before. Steltzner says, “We’re going to a place on Mars called Gale Crater and we’re landing quite literally between a rock and a hard place.”

Nestled inside a protective shell, Curiosity will hit the Martian atmosphere at thirteen thousand miles per hour shedding energy as it falls. But unlike in the past Steltzner says, “This time we’re steering as we fly through the upper atmosphere of Mars and using that steering to shrink our landing uncertainty.”

The next step is to deploy a parachute to further slow the spacecraft. But that only reduces the speed down to two hundred miles per hour. So, the spacecraft is equipped with a kind of jetpack.

“At about two kilometers above the surface, a little less,” says Steltzner, “she lets go of her parachute, turns on the rockets and flies until she’s just twenty meters above the surface. Then twenty meters above the surface the rover is lowered below the jetpack and the two together descend their way to the Martian surface.”

The scientists and engineers determined this was the only feasible landing method to get them to the Gale Crater site inside of which sits a mountain. Steltzer says, “At the end of the day we feel that the net result is a very reliable system. This architecture although it looks challenging really in the end results in a higher reliability, safer way of getting a rover of this size onto the surface of Mars.”

It’s a tight fit, says Manning, “To get there safely though we need to be able to land on the one big flat spot that sits right at the foot of that mountain inside the walls of the crater. Now, if we fly outside of those walls and hit the mountain or the walls of the crater, we’re not in good shape.”

Of course, if it all works, the payoff could be historic. Curiosity is designed to detect the building blocks of life. Scientists think water, a primary ingredient, might at one time have flowed inside the Gale crater. If this Sherlock Holmes of rovers finds that life could have existed on Mars or perhaps still does that could spark a new wave of Mars exploration fever.

With limited exploration dollars in the NASA budget, failure, on the other hand, would put a damper on or perhaps end future robotic exploration of Mars.

Post by:
Filed under: In Space • Mars
soundoff (88 Responses)
  1. w l jones

    When are the scientist going to pull off those blinder and admit all material were produce by some form of life and Mars have pebble and soil similar to that find in Georgia.

    August 6, 2012 at 5:48 pm |
    • Ed


      August 8, 2012 at 1:35 pm |
  2. Cliff

    The should open up a Starbucks and Walmart up there.

    August 6, 2012 at 10:46 am |
    • R. Elko

      Being employed in the aviation maintenance field, and 33 years of aircraft experience, my opinion is the cables will be released through a mechanism that sences weight on wheels, and release imediately.

      August 9, 2012 at 9:12 am |
  3. M Turner

    Can anyone tell me how do they seperate the rover from the cables lowering it ? Thanks

    August 6, 2012 at 9:59 am |
    • cj51

      google this produces many references.
      Here is one:

      August 6, 2012 at 10:24 am |
  4. Percy von Lipinski

    The world is reminded that nobody does it better that the Good Ol' USA and no I'm not an American! Good Luck fingers crossed!
    Much Metta

    August 6, 2012 at 12:12 am |
  5. mikey2ct

    WHERE is the 11:30 PM Sunday coverage ?????????????????yOU ARE SHOWING A RE-RUN!!!!!!!!

    August 5, 2012 at 11:44 pm |
  6. W l jones

    The way our civilization is expanding and millions of miles of highways bounching heat into the atmosphere we better prepare to go to other planet if wont our kind to suvivle.. Mars have everything on it water a thin atmosphere which we have the technolgy to build under ground living quarter and plant desert hardy plant food.

    August 5, 2012 at 11:36 am |
    • tradedate

      Migrating to Mars is not quite that simple. Don't forget, there is no oxygen there.

      August 6, 2012 at 11:15 am |
    • Paul Thwaites

      I have been saying this for years. With what we know is possible we should actively plan to make sure that all of humanity's eggs do NOT remain in one basket. What with nuts having access to WMD's, natural disasters, unknown asteroids (ask the dionosaurs about that one) there are simply too many things that can lead to an Extinction Level Event (ELE). Let us explore ALL possibilities. The world needs NASA to do this and do it well!

      August 6, 2012 at 1:58 pm |
  7. Joseph Ona N.

    May God almight blss America and those involve in this
    humanity project, Amen.

    August 5, 2012 at 8:19 am |
  8. Joseph Ona N.

    God Almight will surely support those involve in this humanity project and bless them,Amen.

    August 5, 2012 at 8:12 am |
  9. Joseph Ona N.

    God ALMIGHTY will surely support& bless America as well as those involve in this humanity project, Amen.

    August 5, 2012 at 8:06 am |
    • Allah AckBarf

      There may not be a God, but there is definitely a Mars. We shall explore to learn and/or to prove.

      Rather than just believe.

      August 6, 2012 at 10:51 am |
      • TruthBtold

        There would not be a Mars without God, it is He who created everything, even you 🙂

        August 6, 2012 at 11:07 am |
      • Raider

        TruthBtold, you mean there wouldn't be Mars without the Almighty Flying Spaghetti Monster. I know you must have accidentally typed in God by mistake, as we all know that the one true Almighty is the FSM!

        August 6, 2012 at 9:17 pm |
  10. helenecha

    What on Earth does it take to support NASA exploration programs? Anyway, ending future robotic exploration of Mars must dampen our interests on Mars' exploration. That’s a shame.

    August 5, 2012 at 2:41 am |
  11. n2video

    No, it's not fog. Probably martian dust kicked up by winds.

    August 4, 2012 at 5:25 pm |
  12. w l jones

    Old picture on Mars clearly shows fog thereby water have to be up their some place.

    August 3, 2012 at 6:15 pm |


  • Elizabeth Landau
  • Sophia Dengo
    Senior Designer